Prefabricated cesspool structure



Sept. 27, 1949.- l.. P. PRIC 2,482,870

` PREFABRICATED CESSPOOL STRUCTURE Filed Nov. l2, 1947 l IN VEN TOR.OU/5 ,0. DQ/CE.

BX l l 2K2@ Patented Sept. 1949 UNITED vSTATES PATENT OFFICEPREFABRICATED CESSPOOL STRUCTURE- Louis P. Price, Honolulu, `Territoryof Hawaii Y Application November 12, 1947, Serial No. 785,463

2 Claims. (Cl. 182-2) tion of uid waste. c

An object of the invention is to provide a cesspool or the likecomprising preformed sectional units which may be arranged as desired toform a structure of any desired capacity and Vwhich may be erected inbut a small fraction of the time employed in the construction of acesspool by the usually-followed procedure.y

Another object of the invention is to provide a cesspool structure whichpermits erection operations to be carried out from operating positionsentirely above the surface of the ground thereby protecting the workmenengaged in the work of installation from the many hazards whichsub-surface excavations entail and releasing them from the usual dutiesof planking and shoring the sides of the excavation to insure againstcave-ins.

A further object of the invention is to provide a sectional cesspoolstructure which when buried in the ground is fully capable ofwithstanding crushing strains such as may be imposed thereon by vehiclesof reasonable weight passing thereover.

Still another object of the invention is to provide a cesspool designedto facilitate outward flow of its fluid contents as the level of thelatter descends due to natural seepage of the fluid into the surroundingsoil.

The invention possesses other objects and features of advantage, some ofwhich, with the foregoing, Will be set forth in the followingdescription of the preferred form of the invention which is illustratedin the drawing accompanying and forming part of the specication. It isto be understood, however, that variations in the showing made by thesaid drawings and description may be adopted within the scope of theinvention as set forth in the claims.

Referring to the drawing:

Figure 1 is a view partly in side elevation and partly in verticalsection showing a cesspool constructed in accordance with the principlesof my invention,

Figure 2 is a perspective view of one section of the cesspool casing.

Figure 3 is a perspective view of one of the intersectional keys.

In many rural and suburban areas, cesspools or septic tanks, as they areoften referred to, are commonly used to dispose of excreta and wastematerials. Such cesspools are usually constructed by excavating in theground at a suit- Lse i able location a, pit of the desired size anddepth,

usually about eight feet in diameter and extending downwardly beyond tenor twelve feet until soil of suitable porous and fluid-conductingcharacteristics is reached. In the pit is then constructed an axiallyvertical tubular casing of natural stone, pressed brick or, in manyinstances, w`ood, the casing being made purposely of a porous nature soas to permit liquid waste which may `subsequently enter theV cesspoolthrough the sewerV pipe leading thereinto to graduallyl seep into thesurrounding soil. A suitable cover is then placed on the casing and theexcavation, exteriorly of the casing and cover is back-filled withearth. It often occurs Vthat the Asoil in which the excavation is madeis of a sandy .stresses tending to crush component parts of thestructure or to cause relative offsetting of some parts relative toothers thereof. I provide a component unit of the structure as shown inFigure 2 comprising a preferably cast concrete casing 4, of circular orother desirable cross-sectional shape, having a bore 6 extending axiallytherethrough and provided with relatively parallel top and bottomsurfaces 1 and 8 respectively. I have found it best to employra casingof at least six feet internal diameter with a wall thickness measuringapproximately four inches, suitable 'reinforcement in the form of wiremesh 9 or the like being molded into the Wall to give the sectionadequate strength against fracture or crumbling during the operations ofhandling, shipping or installation. I provide casing sections in axiallengths of one, two, three and six feet which when combined in anydesired grouping can be made to produce, to the nearest foot, a unitcasing' of any length, The four foot section,

however, is considered as the standard and the drawing and description aunit. Y Y

The bottom end face 8 of the casing section is preferably made as acontinuous unobstructed plane face but the Opposite end face 1 hastherein herein are based on such ly inclined to lie at substantially anangle fof Y forty-five deg-rees with respect to Itl'legaxis ofi-thesection, the uppermost open end of each passage intersecting the boresurface `of the section and being positioned closer to `the `ulcoperface -I than the lower end of the passage. I have found the bestproportions for the openings form-ingthel passages I 3 to be ahorizontal width of about nine inches and a vertical height of .abouttwo and `one-half inches. Also I have found that efficient operationcalls for the provision of horizontal rows of passages spaced vertically.preferably at two-foot centers and with Aeach row containing aboutsixteen passages spaced equidistantly around the casing section.

Installation of the cesspool is effected by excavating an earth bore I4,yas shown in Figure 1, havin-g a diameter vat least one -foot in excessof that of the casing andextending to a depth of one and one-half feetin .excess of the total required depth of the `cesspool casing. Suchexcavation may be conveniently carried out by means of a clamshellbucket operated from above ground level by an automotive crane or othersuitable operating mechanism. In many instances earth will beencountered which is sunlciently compacted to be self-sustaining whilethe excavation is being made Ybut Where the soil is crumbly it may beVnecessary to sink a-sheet metal dam sleeve into the earth as theexcavation progresses so as to .prevent cavingI in of the sides of thebore. In some instances also, the .excavation may extend downwardlybelow the level of the sub-surface water table in which case the use ofthe dam sleeve is imperative. After the excavation has been .completedand the bottom thereof has been substantially levelled, the first casingsection is lowered into place and substantially centered with vthe.earth bore, the notched vend l of the .casing of course beinguppermost. After the aforesaid first section has been .properly set,centering 4keys .1.6, Which are shown in Figure 3, are placed in the keynotches II.

Each key I6 comprises a substantially H-shaped 1 cast concrete bodyhaving a rectangular bar portion II at the opposite ends of which areprovided integral head portions I8 having wings I9 extending oppositelybeyond the top and bottom surfaces of the bar portion. The transversecross-sectional form of the bar portion is made to conform with thevertical cross-sectional area of a key notch II so that `the bar portionwill fit freely into and fill'the key notch. Ihe length of the barportion is slightly in excess of the casing wall thickness so that thewings I9 extend upwardly and downwardly along the inner and outer wallsurfaces of two casing sections which may be placed in superposedcoaxial alignment.

It will be noted that the inner surface 2| of each wing is upwardly andoutwardly inclined with respect to its junction with the top or bottomsurface, as the case may be, of the 'bar portion so as to insure 'tightWedging of the key against the bottom of the 'key notch and against theconfronting bottom surface 8 of the superposed casing section which isnext placed on the previously set section as shown in Figure 1. Theupwardly opening gaps of the placed keys between the upper wings I9thereof cooperate to form a pocket into which the overlyingcasingsection may be moved so as to accurately center and retain the casingsections in alignment. The lowering of the casing sections into`placemay be accomplished by 4a Yrope or cable bridle which may bepassed through upper ones of the Vent passages I3 and which may beattached to the lift line of the crane or other liftling mechanismhereinbefore mentioned.

When as many casing sections have been placed fone on'the other toprovide a chamber of the requiredfdepth, a prefabricated reinforcedcover 23 is placed over the upper end of the casing to fclose Ythelatter. Suitable loops 2@ are provided in the cover to which bridles maybe attached to `place or remove the cover. Also, a plug member 21 isprovided .centrally of the cover which may be removed as desired tofacilitate periodic inspections of .the cesspool chamber. When the coverhas been finally set, the waste line 2G is installed and the peripheralspace around the casing is filled with coarse gravel 22 or other suchporous medium `after which the earth retaining dam sleeve, if any hasbeen used, is removed and the cover l-l 29 of earth is laid over thecover. This completes the installation.

In operation, the fluid vwaste matter entering the cesspool chamberthrough the waste pipe iii will, if the level of ud inthe chamber issui'- ficiently high, flow outwardly and downwardly through the inclinedpassages and will seep through the back ll `2? into the surroundingearth. The `inclination of the passages also serves to lend force to theoutward flow of the fluids, thus maintaining the cesspool .in a betterstate of .clearancethanmight be expected of conventional constructionwherein the fluids would have to find their way through the intersticesbetween loosely laid brick ,cr stone. It will also be seen that theerection of a cesspool constructed in accordance with the :principles ofmy invention refquires only a fraction of the time necessary to .preparefor `and assemble a conventional cesspool; that the resulting structureis much stronger than the usual stone or brick structure and .that allof the construction operations may be carried out above rground levelthus eliminating the hazards generally associated with sub-'terraneanconstruction work of this nature.

I claim:

1. In a cesspool structure, a casing comprising a plurality of preformedtubular cast concrete sections disposed in axially aligned relation tofor-m inner and outer walls of a cesspool chamber, each section havingaxially extending notches lin an end surface thereof and at least one ofsaid sections having downwardly inclined passages extending from thechamber radially outwardly of the wall thereof, H-shaped keys insertiblein said notches having portions extending radiaily beyond said inner andouter walls, said portions having extensions embracing the inner andouter wall Yportions of adjacent sections in said notches and in the endsurface confronting said notches, respectively, for holding therespective sections in relative axial alignment, and a removable cover-engaged `with a-n end surface of a section for closing an end of saidchamber.

2. In a cesspool structure, a, casing comprising a plurality ofsubstantially cylindrical preformed tubular cast concrete sectionsdisposed in axially aligned relation to form inner and outer walls of acesspool chamber, each section having axially extending notches in anend surface thereof and at least one of said sections having downwardlyinclined passages extending from the chamber radially outwardly of thewall thereof, substantially H-shaped keys nsertible in said notcheshaving portions extending radially beyond said inner and outer walls,said portions having extensions embracing the side wall portions ofadjacent sections in said notches and in the end surface confrontingsaid notches, respectively, for

holding the respective sections in relative axial 15 and rotationalalignment.

LOUIS P. PRICE.

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,204,462 Lawrence Nov. 14, 19161,536,000 Hawkins Apr. 28, 1925 1,695,443 Studley Dec. 18, 19282,392,551 Roe Jan. 8, 1946 FOREIGN PATENTS Number Country Date 450,277Great Britain July 14, 1936 699,314 France Dec. 9, 1930

